Tree harvesters for shaking nut and fruit trees to cause nuts or fruit-to drop to the ground for harvesting to are well known in the prior art. R. W. Brandt, Jr. was a prolific inventor in this field and his U.S. Pat. Nos. 3,163,458; 3,220,268; 3,221,567; and 3,318,629 describe various features of tree harvesters and shaker heads that are still used in current devices.
Applicant herein invented a tree shaking machine with automatic sensors described in U.S. Pat. No. 6,658,834, issued on Dec. 9, 2003. This application is an improvement on the machines described in that patent.
When the harvest time of a particular crop occurs, thousands of trees in orchards become ripe at the same time. The shaking of these thousands of trees is a time consuming process, that must be completed quickly, and it is therefore advantageous to create systems that complete the tree shaking operating as quickly as possible, so that more trees can be harvested more rapidly, while the crop is ripe, and before it becomes over ripe and then spoiled. The present invention is an improved automation of the tree harvester shaking process, and it includes tree sensing devices along with a system for automatically deploying the harvester machine and the shaking head, clamping the tree, shaking the tree, releasing the tree and returning the shaker head to the harvester.
Prior U.S. Pat. No. 6,658,834 describes a tree sensing device, mounted upon the harvester. Pre-determined tree distance values and other shaker head control parameters are input into a programmable logic control (PLC) device of the control system. When the harvester is driven to a location next to a tree, the operator initiates an automated tree shaking cycle in which the tree sensor locates the tree and provides distance values to the tree as input signals to the controller. The controller compares the distance values to the tree with the predetermined tree distance value and provides shaker head control signals that cause the shaker head to automatically move outward towards the tree. The shaker head outward motion is halted when the inputted distance values to the tree are equal to or less than the predetermined tree distance values. The control system then provides control signals to the shaker head components to cause the shaker head to clamp the tree, to shake the tree, to unclamp the tree and to move the shaker head back to the harvester. Further control input signals to the controller include engine RPM signals for controlling the engine RPM and tree shaking time signals for controlling the duration of the tree shaking step.